Ursula Marvin

Ursula Marvin Ursula Bailey Marvin (née Bailey; August 20, 1921 – February 12, 2018) was an American pioneering planetary geologist, historian of geology, author of the 1973 book Continental Drift: The Evolution of a Concept, and president for a 2-year term from 1975 to 1976 of the Meteoritical Society. She is memorialized by Antarctica's Taylor Glacier#Marvin Nunatak Marvin Nunatak (named in 1991) and the Moon's Marvin (crater) Marvin Crater (named in 1992). She was elected in 1986 a Fellow of the American Association for the Advancement of Science and received in 2005 the Sue Tyler Friedman Medal. Quotes Mainstream geology is founded upon Uniformitarianism uniformitarian concepts enunciated by James Hutton (1726–1797) and Charles Lyell (1797–1875), who argued that, during unlimited expanses of time, the Earth has undergone slow, ceaseless change by processes we can observe in operation. In their view, we cannot call on any powers that are not natural to the globe, admit of any action of which we do not know the principle, nor allege extraordinary events to explain a common appearance.A Impact event hypervelocity meteorite impact is an extraordinary event, originating from outside the Earth, and wreaking change instantaneously. Such a process violates every tenet of uniformitarianism. Largely for this reason, hypotheses of impact origin for craters on the Earth and the moon were vigorously opposed for the better part of the past century. Space-age research now has established beyond doubt the authenticity of impact as a geologic process, but an abundance of evidence exists that a wide chasm still persists between the views of impact specialists and those of terrestrial geologists. A full realization of the ramifications of impact processes may have been delayed by the advent of plate tectonics, which engulfed the geological community in the late 1960s. Revolutionary as it appeared at that time, plate tectonics, which is envisioned as involving gradual changes generated by forces internal to the globe, fully conforms with uniformitarian principles. In contrast, impact processes, which have recently been cited to account for cataclysmic events such as massive tsunami deposits, incinerating wildfires, and global extinctions, carry genuinely revolutionary implications that are fatal to the uniformitarian principle itself. Chapter 17. Impact and its revolutionary implications for geology by Ursula B. Marvin Global Catastrophes in Earth History; An Interdisciplinary Conference on Impacts, Volcanism, and Mass Mortality Geological Society of America Special Paper 247 Geological Society of America, 1990 9780813722474 https://books.google.com/books?id=eCzsvwEACAAJ&pg=PA147 147–154 10.1130/SPE247-p147 (631 pages from October 1988 conference held in Snowbird, Utah; quote from p. 147; edited by Virgil L. Sharpton and Peter Ward (paleontologist) Peter D. Ward) In August, 1933, at the Field Museum of Natural History in Chicago, The Meteoritical Society The Society for Research on Meteorites was founded with an enrollment of 57 charter members and Frederick C. Leonard and Harvey H. Nininger as the first President and Secretary-Treasurer, respectively. Within five years, the Society had doubled in size, with members from the U.S.A. and ten other nations. Annual meetings were suspended during World War II (1942 through 1945) and when it reconvened in 1946 the members adopted the name “The Meteoritical Society”. By that time personal and professional antagonisms had arisen that threatened to fragment the Society and led, in 1949, to the resignation of Nininger and his wife. Throughout the 1950s the Society was widely regarded as a small, disorganized and essentially moribund organization.Revitalization of the Society began in the early 1960s after the advent of the Space Age when the Society steadily gained members with expertise in mineralogy, petrology, isotope geochemistry, Electron probe microanalysis electron microprobe and neutron activation analysis, and impact dynamics. July 1993 The meteoritical society: 1933 to 1993 Meteoritics 28 3 261–314 https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1945-5100.1993.tb00268.x 10.1111/j.1945-5100.1993.tb00268.x Since the opening of the Space Age, images from spacecraft have enabled us to map the surfaces of all the rocky planets and List of natural satellites satellites in the Solar System, thus transforming them from astronomical to geological objects. This progression of geology from being a strictly Earth science Earth-centred science to one that is planetary-wide has provided us with a wealth of information on the evolutionary histories of other bodies and has supplied valuable new insights on the Earth itself. We have learned, for example, that the Origin of Moon Earth–Moon system most likely formed as a result of a collision in space between the protoearth and a large impactor, and that the Moon subsequently accreted largely from debris of Earth's mantle. The airless, waterless Moon still preserves a record of the impact events that have scarred its surface from the time its crust first formed. The much larger, volcanic Earth underwent a similar bombardment but most of the evidence was lost during the earliest 550 million years or so that elapsed before its first surviving systems of crustal rocks formed. Therefore, we decipher Earth's earliest history by investigating the record on the Moon. Lunar samples collected by the List of Apollo astronauts Apollo astronauts of the USA and the Luna programme robotic Luna missions of the former USSR linked the Earth and Moon by their oxygen isotopic compositions and enabled us to construct a timescale of lunar events keyed to dated samples. They also permitted us to identify certain meteorites as fragments of the lunar crust that were projected to the Earth by impacts on the Moon. Similarly, analyses of the Martian surface soils and atmosphere by the Viking program Viking and Mars Pathfinder Pathfinder missions led to the identification of meteorite fragments ejected by hypervelocity impacts on Mars. Images of Mars displayed land-forms wrought in the past by voluminous floodwaters, similar to those of the long-controversial Channeled Scablands of Washington State, USA. The record on Mars confirmed catastrophic flooding as a significant geomorphic process on at least one other planet. The first views of the Earth photographed by the crew of Apollo 8 gave us the concept of 'Spaceship Earth' and heightened international concern for protection of the global environment. Chapter. Geology: from an Earth to a planetary science in the twentieth century by Ursula B. Marvin The Earth Inside and Out: Some Major Contributions to Geology in the Twentieth Century 2002 9781862390966 Geological Society of London Special Publication No. 192 https://books.google.com.bn/books?id=PFc_SE4dqVMC&pg=PA17 17–57 10.1144/GSL.SP.2002.192.01.03 (369 pages; quote from p. 17; edited by David R. Oldroyd; abstract of chapter) External links In Memoriam: Ursula Marvin March 7, 2018 Cemter for Astrophysics, Harvard University and Smithsonian Institution https://www.cfa.harvard.edu/news/memoriam-ursula-marvin Category:1921 births Category:2018 deaths Category:Astronomers from the United States Category:Geologists from the United States Category:Harvard University alumni Category:People from Vermont Category:Women born in the 1920s Category:Women scientists from the United States